Centralized list of common CMC problems

Really poorly done wiring - many I've looked at have a spaghetti factory going on behind the dash and in the engine compartment.

Tack welded or (much worse) sheet metal screwed-in floor panels.

Seats bolted to the floor panels with no substantial backing metal under the floors for strength (yeah, like four 1/4"-20 bolts are going to hold the seats in in an impact?)

Poor routing of the fuel line/hose, especially in the rear, which allows contact abrasion and/or too close to exhaust pipes (causing vapor lock and worse).

Lack of a positive anchor point for front and rear ends of the steel gas line, allowing it to flap around, fatigue and, eventually, break.

Lack of a front body suspension bracket.  This sits on top of the front torsion bar mounts just ahead of the fuel tank and holds up the nose of the car.  Without it you get both fiberglass fracturing around/near the headlights and at the front bottom corner of the door frame.

The "Infamous CMC Butt Sag" caused, not so much by fatigue of the frame over time (which probably adds slightly to it) but more so by really poor assembly by the "factory" such that the body was just slapped onto the frame and the rear clip riveted to the rear portion of the frame without ever making the door gaps correct in the first place.  Fix is to drill out 6-8 rivets holding the body to the rear frame, jack up the body til the door gaps are straight and even and rivet or bolt it back together.

Check for a wide-area bubble in the fiberglass between the engine cover and the top of the rear cowl - right where one might put a third brake light above the engine cover.  At this age, it will never get any bigger but it sometimes looks a bit odd if you notice it.  They're sometimes 16" across and 8" front to back.  If the top cowl looks as if the line doesn't match the line across the engine cover (like it bulges slightly) then you can live with it or have it taken out and filled.

On the plus side......a lot of CMC's had the thickest fiberglass in the industry and, as a whole, are usually pretty good bodies.  What detracts from a CMC is usually the build quality Which varied widely between (amateur) builders.

Poor panel fitment on the hood and doors. They are not that bad of a replica its just the fact that, as they were sold as a kit makes them all different from one to the next. Spend the time to restore it correctly, cut no corners and spend the cash when you really need to.

The but sag is an easy fix as is the heat shield. There other items will vary. I just finished my CMC and it was a lot of work and took a ton of time but I know what I have now, as I left no stone unturned on the project

Look for poor workmanship from the previous builder and repair the issues. The butt sag will cause cracks to form under the door by the door jamb corner to the rear. The fiberglass is very thick so grind it out and repair it with resin and fiberglass. The rear engine grill looks like #@@%# so you can replace it with one from Stoddards but you need to widen the opening to do so. 

Loose the gauges, and replace them with a better set you will be glad you did. And loom the wiring as good as possible, solder all the connections again you will be glad you did

Make sure the body is fastened to the pan as the manual states !! It will not hurt but will help if you tack weld the outer pan to the frame of the body, as you want all the strength you can get for the floor. Every inch or inch and a half should be good. Seal the crap out of the pan to body joints. I used liquid nails and a paint brush to really pack the joints full and it drys hard and water tight.

Sound deaden the floors, fire wall and doors with dynamat or something like that. 

If you need and other help just ask this forum is full of answers and advice

Get a copy of the build manual - available here to contributing members. Many home builders skip steps and throw supplied parts away. Not sure what is meant by "Constructing a heat shield in the engine bay."  CMC came with fiberglass panels (2) supplied that go over the rear exhaust. The manual covers the rubber seal around the engine and cutting the "moon opening" for air to fan over the flywheel on the firewall and a rubber skirt on the firewall.  

I dislike the "Vintage" brand gauges supplied by CMC as an option but 914, repro 356 or VDO gauges are great options.  The flat door panels scream kit car. The vinyl tonneau and tops are dated but since 20+ years old they are good candidates for upgrade to Haartz cloth ones. Polish the alloy Hibachi grill (a few hours) and it will shine like chrome and never rust. I neverliked the supplied front 18 wheeler marker "turn signal lights - Lucas 494 assemblies are cheap quality fixes.  Wiring is always an issue - but just look at factory wiring in an original VW - it too was a real rats nest right from Wolfsburg!

If you read enough here you'll see issues with brand new VS/JPS which folks just plunked $28k+ down for.  Like waves in fiberglass/paint, Tachs that don't work, overheating engines, oil leaks, clutch problems, and water leaks into interior.   I'm sure Becks and IMs also have some initial teething issues too but you rarely hear from them as they are quickly addressed by the builder.

Here is another one......   Inside each front wheel well, where the windshield area is, there is a fairly large opening from the wheel well into the passenger compartment.....  A sustained drive in rainy conditions will dump quite a bit of water onto the floor pans.....  I plugged mine using "STUFF".....  (Taped up one side and shot the "STUFF:" into the other.) 

Also check the windshield mounting for multiple installations... It could look something like below...

I don't think my CMC has the openings Leon is speaking of.

The interior opening I refferd to is located in the windshield post attachment stud area...  I've seen this on both the CMCs I've worked with....  Maybe a mold change corrected the problem...

It would be around (under) the crater in the last pic...

I just popped a vinyl hole plug in it with some silicon to seal it.  Done.

Leon - Looks like Bonnie and Clyde used that as get-a-way car.  I don't recall seeing opening there on mine but will check it out.  Perhaps its result of one of those multiple test drilling? In the CMC build manual it directs builder to drill where the dimples are in the gel coat.  It seems early castings had those dimples but later bodies were smooth.  On the windshield, I had to call CMC and they faxed me a template to lay on corner and mark for post drilling.  It was a rough draying - actually slightly different dimensions on either side.  I posted here years ago - if someone needs I can re post if SEARCH doesn't bring it up. Lack of dimples GREATLY extended my 40 hour build time (LOL).

This one?

Ted

Yup same stains - I added the measurements in case scanning distorted measurements.

I love that one side is 2 1/4 and the other is 2 3/8. We couldn't split the difference and do 2 5/16 each side?

No, seriously - why not 2 5/16ths each side?

Ted